<template>
  <div class="todo-footer">
    <label>
      <input type="checkbox" v-model="isAll"/>
    </label>
    <span> <span>已完成{{doneCount}}</span> / 全部{{total}} </span>
    <button class="btn btn-danger">清除已完成任务</button>
  </div>
</template>

<script>
  export default {
    // eslint-disable-next-line
    name:'Footer',
    props:['todos','checkAllTodo'],
    computed: {
      // 算总数
      total(){
        return this.todos.length
      },
      // 算已完成的总数
      doneCount(){
        let n = 0
        this.todos.forEach(t => {
          if(t.done){
            n++
          }
        });
        return n
        // return this.todos.reduce((pre,item)=> pre + (item.done ? 1 : 0),0)
      },
      isAll:{
        get(){
          return this.todos.every((t)=>{
            return t.done
          })
        },
        set(value){
          this.checkAllTodo(value)
        }
      }
    }
  }
</script>

<style scoped>
  /*footer*/
.todo-footer {
  height: 40px;
  line-height: 40px;
  padding-left: 6px;
  margin-top: 5px;
}

.todo-footer label {
  display: inline-block;
  margin-right: 20px;
  cursor: pointer;
}

.todo-footer label input {
  position: relative;
  top: -1px;
  vertical-align: middle;
  margin-right: 5px;
}

.todo-footer button {
  float: right;
  margin-top: 5px;
}
</style>